Earthing

[keniff]

Where do you stand with adding circuits to a installation that has the bonding undersized? It's in 6mm and should be 10mm to be up to regs but customer doesn't want it replaced? Can I do the work and advise this should be replaced it's tnc-s

 

[IQ Electrical]

Where do you stand with adding circuits to a installation that has the bonding undersized? It's in 6mm and should be 10mm to be up to regs but customer doesn't want it replaced? Can I do the work and advise this should be replaced it's tnc-s

Can you use the adiabatic to check the bonding size or is this a PME system?

Forget that, I've just seen the TN-C-S !

131.8 explains that before carrying out additions/alterations, the earthing and bonding should be adequate.

You either walk away or you carry out the work on a risk assessed basis, is there any signs of damage from fault currents etc.?

Be absolutely sure to comment on the scenario on your Electrical Installation Certificate.

 

[i=p/u]

what is disconnection time of main fuse?? posted to IQ

 

[IQ Electrical]

what is disconnection time of main fuse?? posted to IQ

It's TN-C-S, 10mm minimum

 

[i=p/u]

even if was in 6mm and means ripping up floors etc..

 

[IQ Electrical]

even if was in 6mm and means ripping up floors etc..

Regulation 999.1: "Where good quality carpeting/flooring is in use, undersized main protective bonding conductors may be utilised where the installation of correctly sized main protective bonding conductors may result in damage to these furnishings"

NOT

 

[Paul.M]

Regulation 999.1: "Where good quality carpeting/flooring is in use, undersized main protective bonding conductors may be utilised where the installation of correctly sized main protective bonding conductors may result in damage to these furnishings"

NOT

And if the above is not observed please note regulation 999.2:- Ensure that you have adequate home insurance to replace your nice furnishings in the event of an electrical fire due to inadequate earthing system.



IQ you should write your own regs, there better than the ones we have now

 

[IQ Electrical]

Thanks Paul!

 

[i=p/u]

he's only jokin

 

[keniff]

IQ so are you saying if the bonding is visibly ok and in place, but say only 6mm you would carry out the work and advise on upgrade?

 

[i=p/u]

like this 1

Regulation 999.1: "Where good quality carpeting/flooring is in use, undersized main protective bonding conductors may be utilised where the installation of correctly sized main protective bonding conductors may result in damage to these furnishings"

NOT

 

[IQ Electrical]

IQ so are you saying if the bonding is visibly ok and in place, but say only 6mm you would carry out the work and advise on upgrade?

Hi Keith,

Your options are as in post 2, if you choose to do the work, make sure you have documented the undersized bonding on your certification and maybe also a covering letter to the client advising of the need to upgrade.

 

[keniff]

Thanks IQ the only bit I didn't understand was carry out the work on a risk assessment basis, i want the work really

 

[Deleted member 26818]

The requirement of BS7671 is to ensure the earthing and bonding arrangements are adequate for the safety measure used.
Adequate does not necessarily mean compliance with BS7671.

 

[ezzzekiel]

pme is a bit awkward

the adiabatic isnt used to size main bonding conductors, use it to size the main earth then the tails and bonds can be sized in relation to this and the size of main service fuse and if adequate then they can be left at 6mm and noted on the eic.